He is the caring brother to Mario. After Mario's beat up by Roxx, he sent a Coffee Mushroom to Mario to save him. He takes responsibility, and when realizing only 1 Coffee Mushroom existed, he made sure to clone more. He got a little action to Roxx. He socked him far into the sky. He hates Toad more than Mario does. Anytime he can talk trash about him he will.
Roxx planned an attack for Ian to kill Luigi. He has to hide from Ian, cause he's a target. He is also able to enter Eggbert's reality. In the reality, his neck is very weird. His life isn't great there however. He also secretly doesn't like Mario, as he had a good dream about kicking his behind.
He has a bald spot on his head. So, he always tries to get products to help with it. Sadly, alot cost too many. He also used to have 2 kidney stones, which were exposed by Benjamin Frankinstein on a video.
Never a good idea to call him Loogini. Eggbert by accident, said it. Eggbert then got attacked and beat up. It happened twice, as Eggbert went to tell Owl. There's a theory that he is gay. He one time was watching some guy in his underwear dancing and twerking, and Mario caught him. Luigi said it isn't what it looks like. The video was loud so Mario told him to help search for Obunga.
He knew Mario 318 was causing trouble with Mario, so after being knocked out, once he woke up, he just pretended to still be knocked out. Once Mario 318 came over, he jumped and knocked him out. He also massacred a load of Galoombas. He killed at least 6 of them. He used this weird black circle item to trick one then jump off of it. Then he threw the item at another. He grabbed an Eris and rolled it down 3 more. Mario 318 soon caught him and locked him up.
He often tries to get out of fights and cowards out, but when it came to the Illuminati, for some reason he did not. He was extremely angry at him. He put up a good fight with him and almost even won. Right before Illuminati was able to win, Luigi did a spin attack and socked him through a ceiling. The spin attack got him out of alot of trouble and was guaranteed dangerous. Seems his cowardness is on and off since he can put up a good fight and be pretty angry. His cowardness shows a lot when Professer E Gadd is shamed or insulted. For some reason he's scared of him being angry.
In the past, he often was crazy and chaotic in adventures with Mario. He often caused trouble or tried to flee the adventure. Mario usually forced him into adventures. As things would start to get more dangerous for Mario, he started to help.